android - 写 Parcelable 对象得到 java.io.NotSerializableException

Question

我有一个名为 Shop 的类，它有 2 个字段和 1 个静态字段。该类实现了Parcelable接口(interface):

public class Shop implements Parcelable{
   private static int SHOP_ID = 12;

   private String name;
   private long fund;

   //constructor with parcel
   public Shop(Parcel parcel){
       name = parcel.readString();
       fund = parcel.readLong();
   }

   //normal constructor
   public Shop(Owner owner){
        name = owner.getShopName();
        fund = owner.getFund();
    }

    @Override
  public int describeContents() {
    return 0;
  }

  @Override
  public void writeToParcel(Parcel dest, int flags) {
      dest.writeString(name);
      dest.writeLong(fund);
    }

    public static final Creator<Shop> CREATOR = new Creator<Shop>(){

       @Override
       public Shop createFromParcel(Parcel parcel) {
        //use the constructor which accept parcel
        return new Shop(parcel);
       }

       @Override
       public Shop[] newArray(int size) {
        return new Shop[size];
       }

    };
}

现在，我的代码使用普通构造函数启动一个 Shop 实例:

Owner owner = getOwnerInfo();
Shop myShop = new Shop(owner); //initiate a Shop with owner

然后，我的代码将 shop 实例存储到 Android 的内部存储中:

String fileName = "shop_file";
try{
  FileOutputStream fos = activity.openFileOutput(fileName,Context.MODE_PRIVATE);
  ObjectOutputStream oos = new ObjectOutputStream(fos);         

  oos.writeObject(myShop); 
  oos.flush();
  oos.close();
}catch(Exception ex){
  ...
}

但是当运行我的应用程序时，我得到了 java.io.NotSerializableException :

06-12 13:04:29.258: W/System.err(2632): java.io.NotSerializableException: com.my.app.model.Shop
06-12 13:04:29.258: W/System.err(2632):     at java.io.ObjectOutputStream.writeNewObject(ObjectOutputStream.java:1364)
06-12 13:04:29.266: W/System.err(2632):     at java.io.ObjectOutputStream.writeObjectInternal(ObjectOutputStream.java:1671)
06-12 13:04:29.266: W/System.err(2632):     at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:1517)

为什么？我哪里错了？

Answer 1

从执行看来，您正在尝试序列化未实现 Serializable 的 CartData 实例:

java.io.NotSerializableException: com.my.app.model.Shop

如果你想序列化它，你应该让 Shop implemensts Serializable

来自doc

Parcel is not a general-purpose serialization mechanism. This class (and the corresponding Parcelable API for placing arbitrary objects into a Parcel) is designed as a high-performance IPC transport. As such, it is not appropriate to place any Parcel data in to persistent storage: changes in the underlying implementation of any of the data in the Parcel can render older data unreadable.